[vtkusers] vtkPolyDataToPolyDataFilter with n inputs - BUG?

[John Biddiscombe]

>The output polyData of the filter has a corrupted time stamp and cannot
>be passed to other filters. In another filter with multiple inputs and

in Execute you should just say
output = this->GetOutput()
the output will be initialized and setup for you, then just do
vtkPoints *outpoints = .....
vtkCellArray *outPolys = ...

and off you go.

Tip. Instead of redefining all the SetInput and SetNthInput, just subclass 
vtkAppendPolyData and override the execute method, that way, when people 
make changes to the input handling etc, you can ignore whats going on.

JB